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86f6a31e | 1 | % \begin{meta-comment} <general public licence> |
2 | %% | |
3 | %% sverb package -- handling of verbatim text | |
8bc5bdd2 | 4 | %% Copyright (c) 1996, 2003, 2007, 2020 Mark Wooding |
86f6a31e | 5 | %% |
3d509049 | 6 | %% This file is part of the `mdwtools' LaTeX package collection. |
86f6a31e | 7 | %% |
3d509049 MW |
8 | %% `mdwtools' is free software: you can redistribute it and/or modify it |
9 | %% under the terms of the GNU General Public License as published by the | |
10 | %% Free Software Foundation; either version 2 of the License, or (at your | |
11 | %% option) any later version. | |
12 | %% | |
13 | %% `mdwtools' is distributed in the hope that it will be useful, but | |
14 | %% WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | %% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | %% General Public License for more details. | |
86f6a31e | 17 | %% |
18 | %% You should have received a copy of the GNU General Public License | |
3d509049 MW |
19 | %% along with `mdwtools'. If not, write to the Free Software Foundation, |
20 | %% Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
86f6a31e | 21 | %% |
22 | % \end{meta-comment} | |
23 | % | |
24 | % \begin{meta-comment} <Package preamble> | |
25 | %<+package>\NeedsTeXFormat{LaTeX2e} | |
26 | %<+package>\ProvidesPackage{sverb} | |
af8af7eb | 27 | %<+package> [2020/09/06 1.14.0 Verbatim typesetting] |
3a9729b4 | 28 | %<+colour>\NeedsTeXFormat{LaTeX2e} |
29 | %<+colour>\ProvidesPackage{svcolour} | |
af8af7eb | 30 | %<+colour> [2020/09/06 1.14.0 Colour support for sverb] |
3a9729b4 | 31 | %<+color>\NeedsTeXFormat{LaTeX2e} |
32 | %<+color>\ProvidesPackage{svcolor} | |
af8af7eb | 33 | %<+color> [2020/09/06 1.14.0 Fix for people who can't spell] |
3a9729b4 | 34 | %<+split>\NeedsTeXFormat{LaTeX2e} |
35 | %<+split>\ProvidesPackage{svsplit} | |
af8af7eb | 36 | %<+split> [2020/09/06 1.14.0 Verbatim, but with line breaking] |
86f6a31e | 37 | % \end{meta-comment} |
38 | % | |
f76fbef3 | 39 | % \CheckSum{1012} |
86f6a31e | 40 | %% \CharacterTable |
41 | %% {Upper-case \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z | |
42 | %% Lower-case \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z | |
43 | %% Digits \0\1\2\3\4\5\6\7\8\9 | |
44 | %% Exclamation \! Double quote \" Hash (number) \# | |
45 | %% Dollar \$ Percent \% Ampersand \& | |
46 | %% Acute accent \' Left paren \( Right paren \) | |
47 | %% Asterisk \* Plus \+ Comma \, | |
48 | %% Minus \- Point \. Solidus \/ | |
49 | %% Colon \: Semicolon \; Less than \< | |
50 | %% Equals \= Greater than \> Question mark \? | |
51 | %% Commercial at \@ Left bracket \[ Backslash \\ | |
52 | %% Right bracket \] Circumflex \^ Underscore \_ | |
53 | %% Grave accent \` Left brace \{ Vertical bar \| | |
54 | %% Right brace \} Tilde \~} | |
55 | %% | |
56 | % | |
57 | % \begin{meta-comment} | |
58 | % | |
59 | %<*driver> | |
60 | \input{mdwtools} | |
61 | \describespackage{sverb} | |
3a9729b4 | 62 | \describespackage{svcolour} |
63 | \describespackage{svsplit} | |
86f6a31e | 64 | \mdwdoc |
65 | %</driver> | |
66 | % | |
67 | % \end{meta-comment} | |
68 | % | |
69 | % \section{User guide} | |
70 | % | |
71 | % The \package{sverb} package provides some useful commands and environments | |
72 | % for doing things with verbatim text. I prefer this code to the standard | |
73 | % \package{verbatim} package (by Rainer Sch\"opf et al.)\ although I'm | |
74 | % biased. | |
75 | % | |
76 | % The package was written to fulfil a particular purpose: I wanted to be able | |
77 | % to typeset ARM assembler code, 77~columns wide, on A5~paper, with the | |
78 | % fields separated by \textit{tab} characters. It's grown up fairly | |
79 | % organically from that, and I've tidied it when I've seen the code get too | |
80 | % ugly. | |
81 | % | |
82 | % The current features are: | |
83 | % | |
84 | % \begin{itemize} | |
85 | % | |
86 | % \item A `listing' environment which typesets verbatim text nicely. | |
87 | % | |
88 | % \item A command to read verbatim text from an external file. | |
89 | % | |
90 | % \item Support for arbitrary-sized chunks of text without overflowing \TeX's | |
91 | % memory. | |
92 | % | |
93 | % \item Support for \textit{tab} characters in the verbatim text. | |
94 | % | |
95 | % \item An environment for typesetting demonstrations of \LaTeX\ markup. | |
96 | % | |
97 | % \item It all works correctly with the \package{doc} system for documenting | |
98 | % \LaTeX\ packages. | |
99 | % | |
100 | % \item A fairly hairy but quite powerful programmer interface to the yukky | |
101 | % bits of the package. | |
102 | % | |
103 | % \end{itemize} | |
104 | % | |
105 | % The interface is described in its own section, so that more timid readers | |
106 | % can avoid it. That said, some of the stuff in this section gets rather | |
107 | % technical. | |
108 | % | |
109 | % Note that this package doesn't even try to do anything with short bits of | |
110 | % verbatim text (as handled by the |\verb:...:| command). I have a separate | |
111 | % package (\package{syntax}) which does all sorts of horrible things along | |
112 | % those lines. | |
113 | % | |
114 | % \subsection{The \env{listing} environment} | |
115 | % | |
116 | % \DescribeEnv{listing} | |
117 | % The main method for typesetting verbatim text is the \env{listing} | |
118 | % environment. This works pretty much the same as the standard | |
119 | % \env{verbatim} environment, with some exceptions, which are described | |
120 | % below. | |
121 | % | |
122 | % So that you know exactly what you're getting, here are the rules by which | |
123 | % \package{sverb} decides what the verbatim text actually is: | |
124 | % | |
125 | % \begin{itemize} | |
126 | % | |
127 | % \item If there's any text, other than spaces, on the same line as the | |
128 | % `|\begin{listing}|', then the contents of the environment begins | |
129 | % immediately after the closing brace (with all leading spaces | |
130 | % preserved). Otherwise, the text begins on the following line. | |
131 | % | |
132 | % \item If there is any text, other than spaces, before the | |
133 | % `|\end{listing}|', but on the same line, this is considered to be the | |
134 | % last line of the text; otherwise the text is presumed to have ended | |
135 | % at the end of the previous line. | |
136 | % | |
137 | % \item Any text following the |\end{listing}| on the same line is thrown | |
138 | % away. There are good reasons for this, but they're technical. | |
139 | % Essentially there's nothing I can do about it. | |
140 | % | |
141 | % \end{itemize} | |
142 | % | |
143 | % \begin{figure} | |
144 | % \begin{demo}[w]{The \env{listing} environment} | |
145 | %\dots in the following code: | |
146 | % | |
147 | %\begin{listing} | |
148 | %init MOV R0,#200 ;Version 2.00 please | |
149 | % LDR R1,=&4B534154 ;Magic number (`TASK') | |
150 | % ADR R2,appName ;Find application name | |
151 | % SWI Wimp_Initialise ;Register as a WIMP task | |
152 | %\end{listing} | |
153 | % | |
154 | %The next step is to \dots | |
155 | % \end{demo} | |
156 | % \end{figure} | |
157 | % | |
158 | % Tab characters are supported within the environment: tab stops are set | |
159 | % every eighth column, although this can be modified. | |
160 | % | |
161 | % \subsubsection{Configuring the \env{listing} environment} | |
162 | % | |
3a9729b4 | 163 | % \DescribeMacro\listingsize |
86f6a31e | 164 | % The text size used in the \env{listing} environment is set by the |
3a9729b4 | 165 | % |\listingsize| command. By default, this is set to |\footnotesize|, |
166 | % although you can redefine it in the document preamble, or it can be set in | |
167 | % the document class. You can put other declarations (e.g., colours) here if | |
168 | % you like. | |
86f6a31e | 169 | % |
3a9729b4 | 170 | % \DescribeMacro\listingindent |
86f6a31e | 171 | % The amount by which the listing text is indented is controlled by the |
172 | % |\listingindent| length parameter. This is a fixed length, whose default | |
173 | % value is 1\,em. | |
174 | % | |
3a9729b4 | 175 | % \DescribeMacro\listinghook |
176 | % \DescribeMacro\svafter | |
177 | % \DescribeMacro\svline | |
178 | % \DescribeMacro\svdoline | |
179 | % \DescribeEnv{listinglist} | |
180 | % The |\listinghook| command is called by the \env{listing} environment (and | |
181 | % |\verbinput| and \env{demo}) to set up the formatting of the listing. It | |
182 | % can do any setting up it likes, and may configure |\svline| and |\svafter| | |
183 | % as necessary. The macro |\svline| is run once for each line of verbatim | |
184 | % text, with the line gathered into a box register, the number of which is | |
185 | % given as an argument. The macro |\svafter| is called when processing has | |
186 | % finished. | |
187 | % | |
188 | % The default setting for |\listinghook| is (similar to) | |
189 | %\begin{listing} | |
190 | %\newcommand{\listinghook}{% | |
191 | % \par% | |
192 | % \begin{listinglist}% | |
193 | % \listingsize% | |
194 | % \renewcommand{\svline}{\listingline}% | |
195 | % \renewcommand{\svafter}{\end{listinglist}}% | |
196 | %} | |
197 | %\end{listing} | |
198 | % (see the source for the true definition). The default |\listingline| macro | |
199 | % just writes out the line using |\svdoline|, which is a simple no-nonsense | |
200 | % macro which just writes the text. As an example, you could say | |
201 | %\begin{listing} | |
202 | %\renewcommand{\listingline}{\leavevmode\llap{\strut\vrule\space}\svdoline} | |
203 | %\end{listing} | |
204 | % to put a rule down the left-hand side of your listings. | |
205 | % | |
206 | % The \env{listinglist} environment is a relatively straightforward | |
207 | % \env{list}-based environment which sets pu the indentation of a listing. | |
208 | % Feel free to redefine it. | |
209 | % | |
86f6a31e | 210 | % \subsubsection{Choosing a different end-text} |
211 | % | |
212 | % \DescribeEnv{listing*} | |
213 | % The \env{listing} environment is terminated by the exact character sequence | |
214 | % `|\end{listing}|'. This isn't too much of a problem, unless you want to | |
215 | % include this string in the text. This is achieved by the \env{listing$*$} | |
216 | % environment, which allows you to specify the end-text to find as an | |
217 | % argument. | |
218 | % | |
219 | % For example: | |
220 | % | |
221 | % \begin{demo}{The \env{listing$*$} environment} | |
222 | %Type a listing as follows: | |
223 | % | |
224 | %\begin{listing*}{<end-listing*>} | |
225 | %\begin{listing} | |
226 | %This is a listing. Yes. | |
227 | %\end{listing} | |
228 | %<end-listing*> | |
229 | %\end{demo} | |
230 | % | |
231 | % Don't include `special' characters in your chosen end-text unless you know | |
232 | % what you're doing. | |
233 | % | |
234 | % \subsection{Writing text to a file} | |
235 | % | |
236 | % \DescribeEnv{verbwrite} | |
237 | % You can write verbatim text to a file using the \env{verbwrite} | |
238 | % environment. The syntax is fairly straightforward: | |
239 | % | |
240 | % \begin{quote} | |
241 | % \syntax{"\\begin{verbwrite}{"<file-name>"}" \dots "\\end{verbwrite}"} | |
242 | % \end{quote} | |
243 | % | |
244 | % The text of the environment is written to the named file. The rules about | |
245 | % where the text actually starts and ends are the same as for the | |
246 | % \env{listing} environment. | |
247 | % | |
248 | % There is also a $*$-variant, like \env{listing$*$}, which allows you to | |
249 | % choose the end-text. The end-text is the first argument, the filename | |
250 | % comes second. | |
251 | % | |
252 | % There is a restriction on the characters you can write to the file: they | |
253 | % must all be considered `printable' by \TeX; otherwise they will be read | |
254 | % back in as `\syntax{"^^"<chars>}' which isn't too good. Unfortunately, | |
255 | % this includes tab characters, so you can't write them.\footnote{^^A | |
256 | % Well, not without doing serious surgery on \TeX\ itself, anyway. } | |
257 | % | |
258 | % \iffalse [Example time... Ho hum. There is evilness here.] \fi | |
259 | %\begin{verbwrite*}{<end-write>}{wrdemo1.tmp} | |
260 | %\begin{verbwrite}{wrdemo.tmp} | |
261 | %This is some text written to | |
262 | %a file near the beginning of | |
263 | %the file. | |
264 | %\end{verbwrite} | |
265 | %<end-write> | |
266 | % | |
267 | % For example: \verbinput{wrdemo1.tmp} | |
268 | % | |
269 | % \input{wrdemo1.tmp} \iffalse [Now build the file ;-) ] \fi | |
270 | % | |
271 | % \subsection{The \cmd\verbinput\ command} | |
272 | % | |
273 | % \DescribeMacro{\verbinput} | |
274 | % You can input a pre-prepared text file exactly as it is in the input using | |
275 | % the |\verbinput| command. The filename is given as an argument. For | |
276 | % example: | |
277 | % | |
278 | % \begin{demo}{The \cmd\verbinput\ command} | |
279 | %\verbinput{wrdemo.tmp} | |
280 | % \end{demo} | |
281 | % | |
282 | % \subsection{The \env{demo} environment} | |
283 | % | |
284 | % Package authors need to document their packages, and it's common to want | |
285 | % to display examples showing the original text and the output side-by-side | |
286 | % (or, when space doesn't permit this, one above the other). Both the | |
287 | % \LaTeX\ book and \textit{The \LaTeX\ Companion} contain such examples. | |
288 | % | |
289 | % The \env{demo} environment allows such displays to be created easily. The | |
290 | % syntax of the environment is as follows: | |
291 | % | |
292 | % \begin{quote} | |
293 | % \syntax{"\\begin{demo}["<shape>"]{"<title>"}" \dots "\\end{demo}"} | |
294 | % \end{quote} | |
295 | % | |
296 | % The optional \synt{shape} argument can be either `|w|' (wide), or `|n|' | |
297 | % (narrow). A `wide' shape places the input and output one above the other, | |
298 | % while the `narrow' shape puts them side-by-side. The default shape is | |
299 | % `narrow'. An attractive border is drawn around the display to finish it | |
300 | % off nicely. | |
301 | % | |
302 | % An example: | |
303 | % | |
304 | %\begin{demo*}{<end-demo>}[w]{The \env{demo} environment} | |
305 | %\begin{demo}{From the \textit{\TeX book}} | |
306 | %\[ \sum_{p\;\rm prime} | |
307 | % f(p) = \int_{t>1} | |
308 | % f(t)\,{\rm d}\pi(t) \] | |
309 | %\end{demo} | |
310 | %<end-demo> | |
311 | % | |
312 | % \DescribeEnv{demo*} | |
313 | % As with the other environments created by this package, there's a | |
314 | % $*$-variant which takes the end-text as an argument. | |
315 | % | |
3a9729b4 | 316 | % \DescribeMacro\demohook |
317 | % The |\demohook| does the same job for \env{demo} environments as | |
318 | % |\listinghook| does for \env{listing}s. The default version just says | |
319 | %\begin{listing} | |
320 | %\newcommand{\demohook}{\setlength{\listingindent}{0pt}\listinghook} | |
321 | %\end{listing} | |
322 | % (near enough), which turns off the indentation for the listing (which would | |
323 | % otherwise look rather odd). | |
324 | % | |
86f6a31e | 325 | % |
326 | % \section{Programmer interface} | |
327 | % | |
328 | % This section describes the publicly available routines provided by the | |
329 | % \package{sverb} package. Routines not described here are libable to be | |
330 | % changed or even removed without warning, so don't use them. | |
331 | % | |
332 | % \subsection{Environment hooks} | |
333 | % | |
334 | % Each of the environments created here works in the same way. For each | |
335 | % environment \env{foo}, there's a main command responsible for doing the | |
336 | % work, called |\sv@foo|. This is given all the arguments of the normal | |
337 | % environment, and two more: | |
338 | % | |
339 | % \begin{itemize} | |
340 | % | |
341 | % \item The `end-text' to search for, which marks the end of the environment. | |
342 | % | |
343 | % \item Some actions to perform after the text has been read and processed. | |
344 | % This allows the calling macro to do some extra actions, like closing | |
345 | % boxes, etc. | |
346 | % | |
347 | % \end{itemize} | |
348 | % | |
349 | % All the environments do is call the main command with appropriate | |
350 | % arguments. | |
351 | % | |
352 | % \subsection{Reading the verbatim text} | |
353 | % | |
354 | % \DescribeMacro{\sv@read} | |
355 | % The main scanning routine is |\sv@read|. It is called with three | |
356 | % arguments: | |
357 | % | |
358 | % \begin{itemize} | |
359 | % | |
360 | % \item The end-text marking the end of the environment. | |
361 | % | |
362 | % \item The name of a macro (which must be a single token) which is called | |
363 | % with a line of text as its single argument. This is given each | |
364 | % line of text which is read from the environment in turn. | |
365 | % | |
366 | % \item A macro, or other sort of action, which is to be done when the text | |
367 | % has been read and processed. | |
368 | % | |
369 | % \end{itemize} | |
370 | % | |
371 | % The macro |\sv@read| assumes that the caller has already made some | |
372 | % provision for removing the category codes of the following text, by either | |
373 | % calling |\@verbatim| or using the construction | |
374 | % \begin{listing} | |
375 | %\let\do=\@makeother | |
376 | %\dospecials | |
377 | % \end{listing} | |
378 | % | |
379 | % \DescribeMacro{\sv@safespc} | |
380 | % Note that any space characters you read using |\sv@read| will be catcoded | |
381 | % as |\active|. Normally this is OK because |\obeyspaces| (or | |
382 | % |\@vobeyspaces|) will be in effect. If you're doing something more exotic, | |
383 | % like writing text to a file or building a command string, you can call | |
384 | % |\sv@safespc| which defines the active-space character to be a normal | |
385 | % whitespace-space when expanded. | |
386 | % | |
3a9729b4 | 387 | % \section{Colour support} |
388 | % | |
389 | % There's now a little colour support in \package{sverb}. To use it, give | |
390 | % the \textsf{colour} (or \textsf{color}) package option, or load the | |
391 | % \package{svcolour} package. | |
392 | % | |
393 | % \DescribeMacro\svcolourline | |
394 | % Say \syntax{"\\svcolourline["<model>"]{"<colour>"}{"<box>"}"} to typeset | |
395 | % \<box> against a background of the given colour. This is a good thing to | |
396 | % put in your |\listingline| command. | |
397 | %\begin{demo}{Coloured listings} | |
398 | %\renewcommand{\listingline} | |
399 | % {\svcolourline[rgb]{1, 0.8, 0.9}} | |
400 | %Consider, for example, this more | |
401 | %complicated program. | |
402 | %\begin{listing} | |
403 | %#include <stdio.h> | |
404 | % | |
405 | %int main(void) | |
406 | %{ | |
407 | % puts("Hello, world!"); | |
408 | % return (0); | |
409 | %} | |
410 | %\end{listing} | |
411 | %\end{demo} | |
412 | % For coloured text rather than background, put a |\color| command in | |
413 | % |\listinghook| itself. | |
414 | % | |
415 | % \section{The \package{svsplit} package} | |
416 | % | |
417 | % A new toy! | |
418 | % | |
419 | % \DescribeEnv{splitverb} | |
420 | % \DescribeEnv{splitverb*} | |
421 | % \DescribeMacro\svsplitchars | |
422 | % The \env{splitverb} environment typesets verbatim material very slowly. On | |
423 | % the plus side, however, it does know how to do simple line-breaking. It | |
424 | % will break lines at spaces or tabs, or after any character listed in | |
425 | % |\svsplitchars|. Continuation lines have the same initial intentation as | |
426 | % the original. If a line has no `good' breaking point, it's broken as late | |
427 | % as possible, and a little hyphen is inserted. | |
428 | %\begin{demo}[w]{The \env{splitverb} environment} | |
429 | %\begin{multicols}{2} | |
430 | %\begin{splitverb} | |
431 | %The \package{url} package is rather fine at splitting up long URLs such as | |
432 | % \url{http://www.excessus.demon.co.uk/tex} | |
433 | %though it can't do its thing in the midst of verbatim text. It | |
434 | %also doesn't cope when | |
435 | % allthespacesinalongphrasehavemysteriouslydisappeared! | |
436 | %\end{splitverb} | |
437 | %\end{multicols} | |
438 | %\end{demo} | |
439 | % | |
86f6a31e | 440 | % \implementation |
441 | % | |
442 | % \section{Implementation} | |
443 | % | |
444 | % This section defines several macros and environments which allow verbatim | |
445 | % typing, with a high degree of configurability. OK, so this sort of | |
446 | % thing's been done so often before that it isn't true, but I don't really | |
447 | % care. | |
448 | % | |
449 | % \begin{macrocode} | |
450 | %<*package> | |
451 | % \end{macrocode} | |
452 | % | |
3a9729b4 | 453 | % \subsection{Options processing} |
454 | % | |
455 | % Notice options, load package. | |
456 | % | |
457 | % \begin{macrocode} | |
458 | \newif\ifsv@colour\sv@colourfalse | |
459 | \DeclareOption{colour}{\sv@colourtrue} | |
460 | \DeclareOption{color}{\sv@colourtrue} | |
461 | \ProcessOptions | |
462 | % \end{macrocode} | |
463 | % | |
86f6a31e | 464 | % \subsection{Simple things} |
465 | % | |
466 | % To help us build funny macros which involve strange and different category | |
467 | % codes, I'll write some simple macros which I can use while building my | |
468 | % complicated and clever ones. | |
469 | % | |
470 | % \begin{macro}{\@cspecials} | |
471 | % | |
472 | % This macro is used to assist the definition of some of the environments. | |
473 | % It makes `|\|', `|{|' and `|}|' into `other' characters, and replaces them | |
474 | % with `\verb"|"', `|<|' and `|>|' respectively. Note that `|[|' and `|]|' | |
475 | % aren't used, because they make defining commands which take optional | |
476 | % arguments awkward. Note that we open a group here. This should be closed | |
477 | % using \verb"|endgroup" at the end of the special section. | |
478 | % | |
479 | % \begin{macrocode} | |
480 | \def\@cspecials{% | |
481 | \begingroup% | |
482 | \catcode`|0% | |
483 | \catcode`<1% | |
484 | \catcode`>2% | |
485 | \catcode`\{12% | |
486 | \catcode`\}12% | |
487 | \catcode`\\12% | |
488 | } | |
489 | % \end{macrocode} | |
490 | % \end{macro} | |
491 | % | |
3a9729b4 | 492 | % \begin{macro}{\sv@addtobox} |
493 | % | |
494 | % Add stuff to a horizontal box. | |
495 | % | |
496 | % \begin{macrocode} | |
497 | \def\sv@addtobox#1#2{\setbox#1\hbox{\unhbox#1\box#2}} | |
498 | % \end{macrocode} | |
499 | % | |
500 | % \end{macro} | |
501 | % | |
502 | % \begin{macro}{\sv@emptybox} | |
503 | % | |
504 | % Clear out a horizontal box. | |
505 | % | |
506 | % \begin{macrocode} | |
507 | \def\sv@emptybox#1{\setbox#1\hbox{}} | |
508 | % \end{macrocode} | |
509 | % | |
510 | % \end{macro} | |
511 | % | |
86f6a31e | 512 | % \begin{macro}{\sv@startlisting} |
513 | % | |
514 | % This macro sets everything up nicely for a \env{listing}-type verbatim | |
515 | % environment. | |
516 | % | |
517 | % \begin{macrocode} | |
518 | \def\sv@startlisting{% | |
519 | \def\par{\@@par\penalty\interlinepenalty}% | |
520 | \@@par% | |
521 | \leftskip\@totalleftmargin% | |
522 | \obeylines% | |
523 | \@noligs% | |
524 | \let\do\@makeother\dospecials% | |
525 | \verbatim@font% | |
526 | \frenchspacing% | |
527 | \@vobeyspaces% | |
528 | \settabwidth% | |
529 | \catcode9\active% | |
530 | \lccode`\~9\lowercase{\let~\sv@vtab}% | |
531 | \lccode`\~13\lowercase{\let~\vinput@cr}% | |
532 | \interlinepenalty500% | |
533 | } | |
534 | % \end{macrocode} | |
535 | % | |
536 | % \end{macro} | |
537 | % | |
538 | % \subsection{Tab character handling} | |
539 | % | |
540 | % One of the things we want to do here is handle tab characters properly. | |
541 | % (Here, `properly' means `moving to the next column which is a multiple of | |
542 | % eight', the way these things were always meant to.) | |
543 | % | |
544 | % \begin{macro}{\settabwidth} | |
545 | % | |
546 | % The tabs used by our tabbed verbatim environments are set up by this | |
547 | % routine. It sets the tab width parameter |\svtab| to 8 times the width | |
548 | % of a |\tt| space. If you really want, you can redefine this macro. | |
549 | % | |
550 | % \begin{macrocode} | |
551 | \newdimen\svtab | |
552 | \def\settabwidth{\setbox\z@\hbox{\texttt{\space}}\svtab8\wd\z@} | |
553 | % \end{macrocode} | |
554 | % | |
555 | % \end{macro} | |
556 | % | |
557 | % \begin{macro}{\sv@vtab} | |
558 | % | |
3a9729b4 | 559 | % Here we handle tabs inside verbatim environments. We expect to be inside |
560 | % |\box|~0. This is padded to the correct width and contributed to |\box|~2; | |
561 | % |\box|~0 is then cleared and re-entered. | |
86f6a31e | 562 | % |
563 | % The idea is that you make tab active, and set it to this macro. We stop | |
564 | % the current box, stretch it to the right width, and start another one | |
3a9729b4 | 565 | % straight after, so nobody knows the difference. The code here is straight |
86f6a31e | 566 | % from Appendix~D of \textit{The \TeX book}. |
567 | % | |
568 | % \begin{macrocode} | |
569 | \def\sv@vtab{% | |
570 | \hfill\egroup% | |
571 | \@tempdima\wd\z@% | |
572 | \divide\@tempdima\svtab% | |
573 | \multiply\@tempdima\svtab% | |
574 | \advance\@tempdima\svtab% | |
575 | \wd\z@\@tempdima% | |
3a9729b4 | 576 | \sv@addtobox\tw@\z@% |
86f6a31e | 577 | \setbox\z@\hbox\bgroup% |
578 | } | |
579 | % \end{macrocode} | |
580 | % | |
581 | % \end{macro} | |
582 | % | |
583 | % \begin{macro}{\verbinput} | |
584 | % | |
585 | % We allow input from a file, by the |\verbinput| command. We display the | |
586 | % text pretty much the same as the \env{listing} environment below. | |
587 | % | |
588 | % We set tab and return active, and get them to do appropriate things. This | |
589 | % isn't actually all that hard. | |
590 | % | |
591 | % \begin{macrocode} | |
3a9729b4 | 592 | \def\verbinput{\listinghook\@ifstar{\verbinput@\@input}{\verbinput@\input}} |
e8e9e5d8 | 593 | \def\verbinput@#1#2{% |
86f6a31e | 594 | \sv@startlisting% |
595 | \setbox\z@\hbox\bgroup% | |
3a9729b4 | 596 | #1{#2}% |
86f6a31e | 597 | \sv@stripspc% |
598 | \egroup% | |
3a9729b4 | 599 | \sv@addtobox\tw@\z@% |
600 | \ifdim\wd\tw@=\z@\listingline\tw@\fi% | |
601 | \svafter% | |
86f6a31e | 602 | } |
603 | % \end{macrocode} | |
604 | % | |
605 | % \end{macro} | |
606 | % | |
607 | % \begin{macro}{\vinput@cr} | |
608 | % | |
609 | % This macro handles return characters while inputting text in |\verbinput|. | |
610 | % We just output our current box, and start another. | |
611 | % | |
612 | % \begin{macrocode} | |
613 | \def\vinput@cr{% | |
614 | \egroup% | |
3a9729b4 | 615 | \sv@addtobox\tw@\z@% |
616 | \listingline\tw@% | |
617 | \sv@emptybox\tw@% | |
86f6a31e | 618 | \setbox\z@\hbox\bgroup% |
619 | } | |
620 | % \end{macrocode} | |
621 | % | |
622 | % \end{macro} | |
623 | % | |
624 | % \subsection{Reading verbatim text} | |
625 | % | |
626 | % The traditional way of reading verbatim text is to use a delimited | |
627 | % argument, as described in the \textit{\TeX book}. This works well-ish if | |
628 | % the text isn't very long. A better solution would be to pick out the text | |
629 | % line-by-line and process it like that. So this is what we do. | |
630 | % | |
631 | % \begin{macro}{\matcher} | |
632 | % | |
633 | % For long verbatim environments, we need to be able to find the end text. | |
634 | % This is rather tricky. The solution here is rather horrible. The | |
635 | % environment picks out each line of the text at a time, as an argument, and | |
636 | % tests to see if it contains the text we're after. We do the test in a | |
637 | % particularly yukky way: we add the actual target text to the end of the | |
638 | % line, and inspect the text following the match to see if the match is at | |
639 | % the end. | |
640 | % | |
641 | % The |\matcher| macro creates a `matcher' which will test strings to see if | |
642 | % they contain something interesting. | |
643 | % | |
644 | % To create a matcher, say | |
645 | % \syntax{"\\matcher{"<cmd-name>"}{"<target>"}{"<process-cmd>"}"}. The | |
646 | % command \synt{cmd-name} accepts a line of text as an argument and calls | |
647 | % the \synt{process-cmd} with the text of the line before the match, or the | |
648 | % whole lot. It also sets |\@ifmatched| appropriately. | |
649 | % | |
650 | % (Having spent ages coming up with this cruft myself, I found some very | |
651 | % similar, but slightly better, code in Appendix~D. So I've changed mine to | |
652 | % match Donald's. Anyway, credit where it's due: cheers Don.) | |
653 | % | |
654 | % \begin{macrocode} | |
655 | \newif\if@matched | |
656 | \def\matcher#1#2#3{% | |
657 | \expandafter\def\csname\string#1$match\endcsname##1#2##2##3\end{% | |
658 | \ifx##2\relax% | |
659 | \@matchedfalse% | |
660 | \else% | |
661 | \@matchedtrue% | |
662 | \fi% | |
663 | #3{##1}% | |
664 | }% | |
665 | \expandafter\def\expandafter#1\expandafter##\expandafter1\expandafter{% | |
666 | \csname\string#1$match\endcsname##1#2\relax\end% | |
667 | }% | |
668 | } | |
669 | % \end{macrocode} | |
670 | % | |
671 | % \end{macro} | |
672 | % | |
673 | % \begin{macro}{\sv@stripspc} | |
674 | % | |
675 | % This macro strips any trailing glue in the current horizontal list. This | |
676 | % is fairly simple, actually: we just loop while glue is the last item. It's | |
677 | % slightly complicated by penalties which \TeX\ puts into the list between | |
678 | % the glue items, but we just remove them too. | |
679 | % | |
680 | % \begin{macrocode} | |
681 | \def\sv@stripspc{% | |
682 | \unpenalty% | |
683 | \ifdim\lastskip=\z@\else% | |
684 | \unskip\expandafter\sv@stripspc% | |
685 | \fi% | |
686 | } | |
687 | % \end{macrocode} | |
688 | % | |
689 | % \end{macro} | |
690 | % | |
691 | % \begin{macro}{\sv@percent} | |
692 | % | |
693 | % This macro strips a single leading percent character if there is one, and | |
694 | % if the \env{doc} package is loaded. We store the possibly stripped text in | |
695 | % |\@tempa|. | |
696 | % | |
697 | % \begin{macrocode} | |
698 | \begingroup | |
699 | \catcode`\%=12 | |
700 | \gdef\sv@percent#1#2\relax | |
701 | {\ifx\check@percent\@@undefined | |
702 | \ifx#1\relax\def\@tempa{}\else | |
703 | \def\@tempa{#1#2}\fi\else | |
704 | \ifx#1\relax\def\@tempa{}\else | |
705 | \ifx#1%\def\@tempa{#2}\else | |
706 | \def\@tempa{#1#2}\fi\fi\fi} | |
707 | \endgroup | |
708 | % \end{macrocode} | |
709 | % | |
710 | % \end{macro} | |
711 | % | |
712 | % \begin{macro}{\@isspaces} | |
713 | % | |
714 | % We want to avoid writing the first and last lines of the environment to the | |
715 | % file if there's nothing in them. To do this, we need to know whether a | |
716 | % piece of text contains only space characters. This macro does this, in a | |
717 | % rather nasty way. See the other macros below for details of how this | |
718 | % works. | |
719 | % | |
720 | % We define |\sv@safespc| at the same time: this makes space active and | |
721 | % expand to a space character which is not active. Neat, huh? | |
722 | % | |
723 | % \begin{macrocode} | |
e7e1adf5 | 724 | \begingroup |
86f6a31e | 725 | \lccode`\~32 |
726 | \lccode`\!32 | |
727 | \lowercase{% | |
e7e1adf5 | 728 | \endgroup |
86f6a31e | 729 | \def\@isspaces#1{% |
730 | \ifx#1\relax% | |
731 | \def\@tempb{\@tempswafalse}% | |
732 | \else\ifx#1~% | |
733 | \let\@tempb\@isspaces% | |
734 | \else% | |
735 | \def\@tempb##1\relax{}% | |
736 | \fi\fi% | |
737 | \@tempb% | |
738 | } | |
739 | \def\sv@safespc{% | |
740 | \catcode32\active% | |
741 | \def~{ }% | |
742 | } | |
743 | } | |
744 | % \end{macrocode} | |
745 | % | |
746 | % \end{macro} | |
747 | % | |
748 | % \begin{macro}{\sv@read} | |
749 | % | |
750 | % This macro does the main job of reading a chunk of verbatim text. You call | |
751 | % it like this: | |
752 | % | |
753 | % \begin{quote} | |
754 | % \syntax{"\\sv@read{"<end-text>"}{"<process-line-proc>"}{"<end-proc>"}"} | |
755 | % \end{quote} | |
756 | % | |
757 | % The \synt{end-text} is the text to find at the end of the `environment': we | |
758 | % stop when we find it. | |
759 | % | |
760 | % The \synt{process-line-proc} is a macro which is passed as an argument each | |
761 | % line which we read from the text. | |
762 | % | |
763 | % The \synt{end-proc} is a macro to call once we've finished reading all of | |
764 | % the text. This can tidy up an environment or close a file or whatever. | |
765 | % | |
766 | % We read the text by picking out newlines using a delimited macro. We have | |
767 | % to be a little clever, because newlines are active in verbatim text. | |
768 | % | |
769 | % We will also strip `|%|' signs off the beginning if the \package{doc} | |
770 | % package is here (\package{doc} tries to play with \LaTeX's verbatim stuff, | |
771 | % and doesn't understand the way we do things). | |
772 | % | |
773 | % \begin{macrocode} | |
774 | \def\sv@read#1#2#3{% | |
775 | % \end{macrocode} | |
776 | % | |
777 | % This code does all sorts of evil things, so I'll start by opening a group. | |
778 | % | |
779 | % \begin{macrocode} | |
780 | \begingroup% | |
781 | % \end{macrocode} | |
782 | % | |
783 | % So that I can spot the end-text, I'll create a matcher macro. | |
784 | % | |
785 | % \begin{macrocode} | |
786 | \matcher\@match{#1}\sv@read@ii% | |
787 | % \end{macrocode} | |
788 | % | |
789 | % So that I can identify line ends, I'll make them active. I'll also make | |
790 | % spaces active so that they can expand to whatever they ought to expand | |
791 | % to (spaces in files, or funny \verb*" " characters or whatever. | |
792 | % | |
793 | % \begin{macrocode} | |
794 | \catcode13\active% | |
795 | \catcode32\active% | |
796 | % \end{macrocode} | |
797 | % | |
798 | % I'll use the |\if@tempswa| flag to tell me whether I ought to output the | |
799 | % current line. This is a little messy, so I'll describe it later. I'll | |
800 | % initialise it to false because this is the correct thing to do. | |
801 | % | |
802 | % \begin{macrocode} | |
803 | \@tempswafalse% | |
804 | % \end{macrocode} | |
805 | % | |
806 | % Most of the job is done by two submacros. I'll define them in terms of | |
807 | % my current arguments (to save lots of token munging). The first just | |
808 | % extracts the next line (which ends at the next newline character) and | |
809 | % tries to match it. | |
810 | % | |
811 | % \begin{macrocode} | |
812 | \lccode`\~13\lowercase{% | |
813 | \def\sv@read@i##1~{\@match{##1}}% | |
814 | }% | |
815 | % \end{macrocode} | |
816 | % | |
817 | % The results of the match get passed here, along with the text of the | |
818 | % line up to the matched text. | |
819 | % | |
820 | % \begin{macrocode} | |
821 | \def\sv@read@ii##1{% | |
822 | % \end{macrocode} | |
823 | % | |
824 | % The first job to do is to maybe strip off percent signs from the beginning, | |
825 | % to keep \package{doc} happy. | |
826 | % | |
827 | % \begin{macrocode} | |
828 | \sv@percent##1\relax\relax% | |
829 | % \end{macrocode} | |
830 | % | |
831 | % Now I need to decide whether I ought to output this line. The method goes | |
832 | % like this: if this is the first line (|\if@tempswa| is false) or the last | |
833 | % (|\if@matched| is true), \emph{and} the text consists only of spaces, then | |
834 | % I'll ignore it. | |
835 | % | |
836 | % The first thing to do is to notice the last line -- if |\if@matched| is | |
837 | % true, then I'll make |\if@tempswa| false to make the first-line and | |
838 | % last-line cases work the same way. | |
839 | % | |
840 | % \begin{macrocode} | |
841 | \if@matched\@tempswafalse\fi% | |
842 | % \end{macrocode} | |
843 | % | |
844 | % Now if this is the first or last line, I'll examine it for spaces. This | |
845 | % is done in a separate macro. It will set |\if@tempswa| false if the | |
846 | % text contains only spaces. | |
847 | % | |
848 | % \begin{macrocode} | |
849 | \if@tempswa\else\@tempswatrue\expandafter\@isspaces\@tempa\relax\fi% | |
850 | % \end{macrocode} | |
851 | % | |
852 | % Now, if |\if@tempswa| is still true, perform the \<process-line-proc> on | |
853 | % the line of text. I'll provide a group, so that it doesn't upset me | |
854 | % too much. | |
855 | % | |
856 | % \begin{macrocode} | |
857 | \if@tempswa% | |
858 | \begingroup% | |
859 | \expandafter#2\expandafter{\@tempa}% | |
860 | \endgroup% | |
861 | \fi% | |
862 | % \end{macrocode} | |
863 | % | |
864 | % The next line won't be the first one, so I'll set the flag true in | |
865 | % readiness. | |
866 | % | |
867 | % \begin{macrocode} | |
868 | \@tempswatrue% | |
869 | % \end{macrocode} | |
870 | % | |
871 | % Now, if that wasn't the last line, go round again; otherwise end the group | |
872 | % I started ages ago, and do the user's \<end-proc>. | |
873 | % | |
874 | % \begin{macrocode} | |
875 | \if@matched\def\@tempa{\endgroup#3}\else\let\@tempa\sv@read@i\fi% | |
876 | \@tempa% | |
877 | }% | |
878 | % \end{macrocode} | |
879 | % | |
880 | % Now to start the thing up. I'll read the first line. | |
881 | % | |
882 | % \begin{macrocode} | |
883 | \sv@read@i% | |
884 | } | |
885 | % \end{macrocode} | |
886 | % | |
887 | % \end{macro} | |
888 | % | |
889 | % \begin{macro}{\sv@readenv} | |
890 | % | |
891 | % This macro works out an appropriate end-text for the current environment. | |
892 | % If you say \syntax{"\\sv@readenv{"<macro-name>"}"}, it will expand do | |
893 | % \begin{listinglist} \listingsize \synshorts | |
894 | % <macro-name>"{\\"$_{12}$"end{"$_{12}$<current-env-name>"}"$_{12}$"}"^^A | |
eafdddad | 895 | % "{\\end{"<current-env-name>"}}" |
86f6a31e | 896 | % \end{listinglist} |
897 | % Easy, no? | |
898 | % | |
899 | % This is all done with mirrors. No, err\dots\ it's done with | |
900 | % |\expandafter|. | |
901 | % | |
902 | % \begin{macrocode} | |
903 | \begingroup | |
904 | \lccode`\<=`\{ | |
905 | \lccode`\>=`\} | |
906 | \lccode`\|=`\\ | |
907 | \lowercase{\endgroup | |
3a9729b4 | 908 | \def\sv@readenv#1{\expandafter\sv@readenv@i\expandafter{\@currenvir}{#1}} |
909 | \def\sv@readenv@i#1#2{#2{|end<#1>}{\end{#1}}} | |
86f6a31e | 910 | } |
911 | % \end{macrocode} | |
912 | % | |
913 | % \end{macro} | |
914 | % | |
915 | % \begin{macro}{\sv@verbline} | |
916 | % | |
917 | % This macro typesets a line in a verbatim way, so you can construct a real | |
918 | % verbatim environment from it. It's a bit tricky in the way that it catches | |
919 | % the last line. Don't worry about this: it's easy really. Note the | |
920 | % |\relax| after the |\par| -- this is because \package{doc} tries to do | |
921 | % clever things with |\par| to strip `|%|' signs out. | |
922 | % | |
923 | % \begin{macrocode} | |
924 | \def\sv@verbline#1{% | |
3a9729b4 | 925 | \sv@emptybox\tw@% |
86f6a31e | 926 | \setbox\z@\hbox{#1\sv@stripspc}% |
3a9729b4 | 927 | \sv@addtobox\tw@\z@% |
928 | \if1\ifdim\wd\tw@=\z@\if@matched0\else1\fi\else1\fi% | |
929 | \svline\tw@\relax% | |
86f6a31e | 930 | \fi% |
931 | } | |
932 | % \end{macrocode} | |
933 | % | |
934 | % \end{macro} | |
935 | % | |
936 | % \subsection{Listing environments} | |
937 | % | |
938 | % The \env{listing} environment is our equivalent of the standard | |
939 | % \env{verbatim} environment. We do some slightly cleverer things, though, | |
940 | % to make sure (for example) that even text which contains |\end{listing}| | |
941 | % can be typeset. | |
942 | % | |
3a9729b4 | 943 | % \begin{macro}{\listinghook} |
944 | % | |
945 | % Set everything up as required. This is here for customization. The | |
946 | % underlying machinery doesn't mess with this directly, but assumes that | |
947 | % |\svline| and |\svafter| are set up appropriately. | |
948 | % | |
949 | % \begin{macrocode} | |
950 | \def\listinghook{% | |
951 | \par% | |
952 | \begingroup | |
953 | \listinglist% | |
954 | \listingsize% | |
955 | \let\svline\listingline% | |
956 | \def\svafter{\endlistinglist\endgroup}% | |
957 | } | |
958 | % \end{macrocode} | |
959 | % | |
960 | % \end{macro} | |
961 | % | |
86f6a31e | 962 | % \begin{macro}{\listinglist} |
963 | % \begin{environment}{listinglist} | |
964 | % | |
965 | % This defines the layout for the \env{listing} environment. It starts a | |
966 | % list with the appropriate shape. It's also made into an environment, so | |
967 | % that the end-paragraph-environment bits work correctly. | |
968 | % | |
969 | % The |\listingindent| length parameter sets up the indentation of the | |
970 | % listings. If there's a |\parindent| setting, I'll line listings up with | |
971 | % that; otherwise I'll just choose something which looks right. | |
972 | % | |
973 | % \begin{macrocode} | |
974 | \newdimen\listingindent | |
975 | \AtBeginDocument{% | |
976 | \ifdim\parindent=\z@\listingindent1em\else\listingindent\parindent\fi% | |
977 | } | |
978 | % \end{macrocode} | |
979 | % | |
980 | % Now to define a size hook for the environment. This is fairly simple | |
981 | % stuff. | |
982 | % | |
983 | % \begin{macrocode} | |
984 | \ifx\listingsize\@@undefined | |
3a9729b4 | 985 | \let\listingsize\footnotesize |
86f6a31e | 986 | \fi |
987 | % \end{macrocode} | |
988 | % | |
989 | % Now to define the environment itself. Suppress the indentation if we're | |
990 | % first thing on a new list item, so that the listing lines up with | |
991 | % everything else. | |
992 | % | |
993 | % \begin{macrocode} | |
994 | \def\listinglist{% | |
995 | \list{}{% | |
996 | \if@inlabel% | |
997 | \leftmargin\z@% | |
998 | \else% | |
999 | \leftmargin\listingindent% | |
1000 | \fi% | |
1001 | \rightmargin\z@% | |
1002 | \labelwidth\z@% | |
1003 | \labelsep\z@% | |
1004 | \itemindent\z@% | |
1005 | \listparindent\z@% | |
1006 | \let\makelabel\relax% | |
1007 | \parsep\z@skip% | |
1008 | }% | |
1009 | \parfillskip\@flushglue% | |
1010 | \item\relax% | |
1011 | } | |
1012 | \let\endlistinglist\endlist | |
1013 | % \end{macrocode} | |
1014 | % | |
1015 | % \end{environment} | |
1016 | % \end{macro} | |
1017 | % | |
3a9729b4 | 1018 | % \begin{macro}{\svline} |
1019 | % \begin{macro}{\svdoline} | |
1020 | % \begin{macro}{\listingline} | |
1021 | % | |
1022 | % The simple spit-out-a-line macro. | |
1023 | % | |
1024 | % \begin{macrocode} | |
1025 | \def\svdoline#1{\leavevmode\box#1\par} | |
1026 | \let\svline\svdoline | |
1027 | \let\listingline\svline | |
1028 | % \end{macrocode} | |
1029 | % | |
1030 | % \end{macro} | |
1031 | % \end{macro} | |
1032 | % \end{macro} | |
1033 | % | |
1034 | % \begin{macro}{\svafter} | |
1035 | % | |
1036 | % This is called when the machinery finishes. A default is set for safety's | |
1037 | % sake. | |
1038 | % | |
1039 | % \begin{macrocode} | |
1040 | \let\svafter\relax | |
1041 | % \end{macrocode} | |
1042 | % | |
1043 | % \end{macro} | |
1044 | % | |
86f6a31e | 1045 | % \begin{environment}{listing} |
1046 | % | |
1047 | % The \env{listing} environment is the only real verbatim-like environment we | |
1048 | % create will all this kit, although it does the job very nicely. | |
1049 | % | |
1050 | % The environment indents its contents slightly, unlike \env{verbatim}, and | |
1051 | % uses a smaller typeface in an attempt to fit 77-column text on an A5~page. | |
1052 | % There is also a $*$-variant, which allows you to specify the terminating | |
1053 | % text. This enables you to include absolutely any text in the environment, | |
1054 | % including |\end{listing}|. | |
1055 | % | |
1056 | % First, we must define the |\listing| command. | |
1057 | % | |
1058 | % \begin{macrocode} | |
3a9729b4 | 1059 | \def\listing{\listinghook\sv@readenv\sv@listing} |
86f6a31e | 1060 | % \end{macrocode} |
1061 | % | |
1062 | % Now we define the |\@listing| command, which does most of the work. We | |
1063 | % base the \env{listing} environment on a \env{list}. | |
1064 | % | |
1065 | % \begin{macrocode} | |
3a9729b4 | 1066 | \def\sv@listing#1#2{\sv@startlisting\sv@read{#1}\sv@verbline{\svafter#2}} |
86f6a31e | 1067 | % \end{macrocode} |
1068 | % | |
1069 | % Now we define the starred version. The command name needs to include the | |
1070 | % `|*|' character, so we must use |\csname|. There's some hacking here to | |
1071 | % allow us to read the name using the appropriate catcodes for otherwise | |
1072 | % normal characters: \LaTeX\ activates some characters and makes them typeset | |
1073 | % themselves to suppress some ligaturing. | |
1074 | % | |
1075 | % \begin{macrocode} | |
1076 | \expandafter\def\csname listing*\endcsname{% | |
3a9729b4 | 1077 | \listinghook\begingroup\@noligs\listing@star% |
86f6a31e | 1078 | } |
3a9729b4 | 1079 | \def\listing@star#1{\endgroup\sv@listing{#1}{\end{listing*}}} |
86f6a31e | 1080 | % \end{macrocode} |
1081 | % | |
1082 | % \end{environment} | |
1083 | % | |
1084 | % \begin{environment}{ignore} | |
1085 | % | |
1086 | % The \env{ignore} environment entirely ignores its contents. Anything at | |
1087 | % all may be put into the environment: it is discarded utterly. | |
1088 | % | |
1089 | % We define some macros for defining ignoring environments, because this can | |
1090 | % be useful for version control, possibly. | |
1091 | % | |
1092 | % \begin{macrocode} | |
1093 | \def\sv@ignore#1#2{% | |
1094 | \@bsphack% | |
1095 | \let\do\@makeother\dospecials% | |
1096 | \sv@read{#1}\@gobble{\@esphack#2}% | |
1097 | } | |
1098 | \def\ignore{\sv@readenv\sv@ignore} | |
1099 | \def\ignoreenv#1{% | |
1100 | \expandafter\let\csname #1\endcsname\ignore% | |
1101 | } | |
1102 | \def\unignoreenv#1{% | |
1103 | \expandafter\def\csname #1\endcsname{\endgroup}% | |
1104 | \expandafter\def\csname end#1\endcsname% | |
1105 | {\begingroup\def\@currenvir{#1}}% | |
1106 | } | |
1107 | % \end{macrocode} | |
1108 | % | |
1109 | % \end{environment} | |
1110 | % | |
1111 | % \subsection{The \env{verbwrite} environment} | |
1112 | % | |
1113 | % The \env{verbwrite} environment allows text to be written to a file in a | |
1114 | % verbatim way. Note that tab characters don't work, because \TeX\ refuses | |
1115 | % to be nice. | |
1116 | % | |
1117 | % \begin{macro}{\sv@write} | |
1118 | % | |
1119 | % As seems to be traditional now, we first define a general hookable macro | |
1120 | % which allows a caller to specify the end-text and what to do afterwards. | |
1121 | % | |
1122 | % \begin{macrocode} | |
1123 | \newwrite\sv@writefile | |
1124 | \def\sv@write#1#2{% | |
1125 | \begingroup% | |
1126 | \@bsphack% | |
1127 | \let\do\@makeother\dospecials% | |
1128 | \sv@safespc% | |
1129 | \sv@read{#1}\sv@writeline{\sv@endwrite#2}% | |
1130 | } | |
1131 | \def\sv@writeline#1{% | |
1132 | \immediate\write\sv@writefile{#1}% | |
1133 | } | |
1134 | \def\sv@endwrite{% | |
1135 | \@esphack% | |
1136 | \endgroup% | |
1137 | } | |
1138 | % \end{macrocode} | |
1139 | % | |
1140 | % \end{macro} | |
1141 | % | |
1142 | % \begin{environment}{verbwrite} | |
1143 | % | |
1144 | % Now we can define the actual environment. We define a $*$-variant which | |
1145 | % allows the user to specify the end-text, just to make sure. | |
1146 | % | |
1147 | % \begin{macrocode} | |
1148 | \def\verbwrite#1{% | |
1149 | \immediate\openout\sv@writefile#1\relax% | |
1150 | \sv@readenv\sv@write% | |
1151 | } | |
1152 | \def\endverbwrite{\immediate\closeout\sv@writefile} | |
1153 | \expandafter\def\csname verbwrite*\endcsname#1#2{% | |
1154 | \immediate\openout\sv@writefile#2\relax% | |
1155 | \sv@write{#1}{\immediate\closeout\sv@writefile\end{verbwrite*}}% | |
1156 | } | |
1157 | % \end{macrocode} | |
1158 | % | |
1159 | % \end{environment} | |
1160 | % | |
1161 | % \subsection{The \env{demo} environment} | |
1162 | % | |
1163 | % By way of tying all of this together, I present an environment for | |
1164 | % displaying demonstrations of \LaTeX\ markup. We read the contents of the | |
1165 | % environment, write it to a temporary file, and read it back twice, | |
1166 | % typesetting it the first time and displaying it verbatim the second time. | |
1167 | % | |
1168 | % \begin{macro}{\sv@demoname} | |
1169 | % | |
1170 | % This macro expands to the filename to use for the temporary data. To | |
1171 | % allow the package documentation to demonstrate the \env{demo} environment | |
1172 | % itself, we need to keep a nesting count. This avoids too much hackery, | |
1173 | % which unfortunately appears to plague all of my \TeX\ code. | |
1174 | % | |
1175 | % \begin{macrocode} | |
1176 | \newcount\sv@nestcount | |
f76fbef3 | 1177 | \def\sv@demoname{\jobname-demo\number\sv@nestcount.tmp} |
86f6a31e | 1178 | % \end{macrocode} |
1179 | % | |
1180 | % \end{macro} | |
1181 | % | |
1182 | % \begin{macro}{\sv@demo} | |
1183 | % | |
1184 | % As for listing, we do all the business through a private macro. This is | |
1185 | % good because it means we can leave the main macro readable. The argument | |
1186 | % is the end-text to spot. | |
1187 | % | |
1188 | % \begin{macrocode} | |
1189 | \def\sv@demo#1#2{% | |
1190 | \@ifnextchar[{\sv@demo@i{#1}{#2}}{\sv@demo@i{#1}{#2}[n]}% | |
1191 | } | |
1192 | \def\sv@demo@i#1#2[#3]#4{% | |
1193 | \advance\sv@nestcount by\@ne% | |
1194 | \immediate\openout\sv@writefile\sv@demoname\relax% | |
1195 | \sv@write{#1}{% | |
1196 | \immediate\closeout\sv@writefile% | |
1197 | \sv@dodemo{#2}{#3}{#4}% | |
1198 | }% | |
1199 | } | |
1200 | % \end{macrocode} | |
1201 | % | |
1202 | % \end{macro} | |
1203 | % | |
1204 | % \begin{environment}{demo} | |
1205 | % | |
1206 | % This is the real environment. We provide \env{demo$*$} too, to allow the | |
1207 | % user to choose the end-text. | |
1208 | % | |
1209 | % \begin{macrocode} | |
3a9729b4 | 1210 | \def\demo{\let\@demohook\demohook\sv@readenv\sv@demo} |
1211 | \expandafter\def\csname demo*\endcsname#1% | |
1212 | {\let\@demohook\demohook\sv@demo{#1}{\end{demo*}}} | |
86f6a31e | 1213 | % \end{macrocode} |
1214 | % | |
1215 | % \end{environment} | |
1216 | % | |
3a9729b4 | 1217 | % \begin{macro}{\demohook} |
1218 | % | |
1219 | % Like |\listinghook|. So much so that we just call it, but first ensure | |
1220 | % that the indent is zero (otherwise it looks really odd!). | |
1221 | % | |
1222 | % \begin{macrocode} | |
1223 | \def\demohook{\listingindent\z@\listinghook} | |
1224 | % \end{macrocode} | |
1225 | % | |
1226 | % \end{macro} | |
1227 | % | |
86f6a31e | 1228 | % \begin{macro}{\sv@dodemo} |
1229 | % | |
1230 | % First, let's define some common bits of code in the stuff below. The | |
1231 | % minipages used to typeset the material has some clever stuff to avoid | |
1232 | % strange spacing in the output. | |
1233 | % | |
1234 | % \begin{macrocode} | |
1235 | \def\sv@demosmp{% | |
1236 | \begin{minipage}[t]{\@tempdima}% | |
1237 | \vskip8\p@% | |
1238 | \hrule\@height\z@% | |
1239 | \raggedright% | |
1240 | \vbox\bgroup% | |
1241 | } | |
1242 | \def\sv@demoemp{% | |
1243 | \par\unpenalty\unskip% | |
1244 | \egroup% | |
1245 | \vskip8\p@% | |
1246 | \hrule\@height\z@% | |
1247 | \end{minipage}% | |
1248 | } | |
1249 | % \end{macrocode} | |
1250 | % | |
1251 | % This is the macro which actually typesets the demonstration. | |
1252 | % | |
1253 | % \begin{macrocode} | |
1254 | \def\sv@dodemo#1#2#3{% | |
1255 | % \end{macrocode} | |
1256 | % | |
1257 | % Now work out some values. We set |\hsize| to the line width leaving 2\,em | |
1258 | % of space on either side. The size of the minipages is calculated depending | |
1259 | % on the shape of the demonstration. This is all fairly simple. | |
1260 | % | |
1261 | % \begin{macrocode} | |
1262 | \begingroup% | |
1263 | \@tempdima\linewidth% | |
1264 | \advance\@tempdima-2em% | |
1265 | \hsize\@tempdima% | |
1266 | \if#2w% | |
1267 | \advance\@tempdima-2em% | |
1268 | \else% | |
1269 | \advance\@tempdima-3em% | |
1270 | \divide\@tempdima2% | |
1271 | \fi% | |
1272 | % \end{macrocode} | |
1273 | % | |
1274 | % Now we open a big vertical box, and put in a header to mark off the | |
1275 | % demonstration. | |
1276 | % | |
1277 | % \begin{macrocode} | |
1278 | \par% | |
1279 | \setbox\z@\hbox{\strut\enspace#3\enspace\strut}% | |
1280 | \@tempdimb.5\dp\z@% | |
1281 | \advance\@tempdimb-.5\ht\z@% | |
1282 | \ht\z@\@tempdimb\dp\z@\@tempdimb% | |
1283 | \noindent\hskip1em\vtop{% | |
1284 | \hb@xt@\hsize{% | |
1285 | \hrulefill% | |
1286 | \raise\@tempdimb\box\z@% | |
1287 | \hrulefill% | |
1288 | }% | |
1289 | \nointerlineskip% | |
1290 | \hb@xt@\hsize{\vrule\@height5\p@\hfil\vrule\@height5\p@}% | |
1291 | \nointerlineskip% | |
1292 | % \end{macrocode} | |
1293 | % | |
1294 | % Now we insert the output text in the first minipage. I'll force `|%|' | |
1295 | % to be a comment character, in case something like \package{doc} has had its | |
1296 | % wicked way. | |
1297 | % | |
1298 | % \begin{macrocode} | |
1299 | \vskip-\parskip% | |
1300 | \noindent\hbox{}\hskip1em% | |
1301 | \sv@demosmp% | |
1302 | \catcode`\%14\relax% | |
3a9729b4 | 1303 | \@input{\sv@demoname}% |
86f6a31e | 1304 | \sv@demoemp% |
1305 | % \end{macrocode} | |
1306 | % | |
1307 | % Insert some kind of separation between the two. In `wide' format, we start | |
1308 | % a new line, and put a ruleoff between the two. In `narrow' format, we just | |
1309 | % leave some space. | |
1310 | % | |
1311 | % \begin{macrocode} | |
1312 | \if#2w% | |
1313 | \vskip8\p@\hrule\vskip8\p@% | |
1314 | \noindent\hbox{}% | |
1315 | \fi% | |
1316 | \hskip1em% | |
1317 | % \end{macrocode} | |
1318 | % | |
1319 | % Now we put the verbatim copy of the text in the other minipage. | |
1320 | % | |
1321 | % \begin{macrocode} | |
1322 | \sv@demosmp% | |
3a9729b4 | 1323 | \@demohook% |
1324 | \verbinput@\@input\sv@demoname% | |
86f6a31e | 1325 | \sv@demoemp% |
1326 | \par% | |
1327 | \nointerlineskip% | |
1328 | \hb@xt@\hsize{\vrule\@height5\p@\hfil\vrule\@height5\p@}% | |
1329 | \hrule% | |
1330 | }% | |
1331 | \endgroup% | |
1332 | \par% | |
1333 | \vskip\baselineskip% | |
1334 | #1% | |
1335 | } | |
1336 | % \end{macrocode} | |
1337 | % | |
1338 | % \end{macro} | |
1339 | % | |
3a9729b4 | 1340 | % \subsection{Loading the colour package} |
1341 | % | |
1342 | % If requested, we load the \package{svcolour} package here. This ensures | |
1343 | % that it can patch this code if it needs to. | |
1344 | % | |
1345 | % \begin{macrocode} | |
1346 | \ifsv@colour | |
1347 | \RequirePackage{svcolour} | |
1348 | \fi | |
1349 | % \end{macrocode} | |
1350 | % | |
86f6a31e | 1351 | % That's all there is. Have fun. |
1352 | % | |
1353 | % \begin{macrocode} | |
1354 | %</package> | |
1355 | % \end{macrocode} | |
1356 | % | |
3a9729b4 | 1357 | % \subsection{The \package{svcolour} package} |
1358 | % | |
1359 | % This is in a separate package to avoid dragging in the \package{color} | |
1360 | % package if it's unwanted. | |
1361 | % | |
1362 | % I prefer English spellings. Here's a trivial redirection for Americans. | |
1363 | % | |
1364 | % \begin{macrocode} | |
1365 | %<*color> | |
1366 | \DeclareOption*{\PassOptionsToPackage{\CurrentOption}{svcolour}} | |
1367 | \ProcessOptions | |
1368 | \RequirePackage{svcolour} | |
1369 | %</color> | |
1370 | % \end{macrocode} | |
1371 | % | |
1372 | % And now we can start the thing properly. | |
1373 | % | |
1374 | % \begin{macrocode} | |
1375 | %<*colour> | |
1376 | \RequirePackage{color} | |
1377 | % \end{macrocode} | |
1378 | % | |
1379 | % \begin{macro}{\@snarfcolour} | |
1380 | % | |
1381 | % Reading a colour specification is something we'll need to do a few times, | |
1382 | % so an abstraction is useful. Its single argument is a continuation to | |
1383 | % which we pass a colour-spec acceptable to the |\color| command. (This is | |
1384 | % the same code as found in the \package{mdwtab} package. Remember to keep | |
1385 | % them in step.) | |
1386 | % | |
1387 | % \begin{macrocode} | |
1388 | \def\@snarfcolour#1{% | |
1389 | \@ifnextchar[{\@snarfcolour@i{#1}}{\@snarfcolour@ii{#1}{}}% | |
1390 | } | |
1391 | \def\@snarfcolour@i#1[#2]{\@snarfcolour@ii{#1}{[#2]}} | |
1392 | \def\@snarfcolour@ii#1#2#3{#1{#2{#3}}} | |
1393 | % \end{macrocode} | |
1394 | % | |
1395 | % \end{macro} | |
1396 | % | |
1397 | % \begin{macro}{\svcolourline} | |
1398 | % \begin{macro}{\svcolorline} | |
1399 | % | |
1400 | % Snarf the option, and plot the coloured bar. Note the penalties which are | |
1401 | % meant to stick the glue and leaders onto the colour specials. | |
1402 | % | |
1403 | % \begin{macrocode} | |
1404 | \def\svcolourline{\@snarfcolour\svcl@i} | |
1405 | \def\svcl@i#1#2{% | |
1406 | \skip@\wd#2% | |
1407 | \advance\skip@\parfillskip% | |
1408 | \advance\skip@.2em% | |
1409 | \strut% | |
1410 | \kern.2em% | |
1411 | \begingroup\color#1\nobreak\leaders\vrule\hskip\skip@\endgroup% | |
1412 | \nobreak\hskip-\skip@% | |
1413 | \kern.2em% | |
1414 | \box#2% | |
1415 | \nobreak\hskip-\rightskip\vadjust{}% | |
1416 | \par% | |
1417 | } | |
1418 | \let\svcolorline\svcolourline | |
1419 | % \end{macrocode} | |
1420 | % | |
1421 | % \end{macro} | |
1422 | % \end{macro} | |
1423 | % | |
1424 | % Done! | |
1425 | % | |
1426 | % \begin{macrocode} | |
1427 | %</colour> | |
1428 | % \end{macrocode} | |
1429 | % | |
1430 | % \subsection{The \package{svsplit} package} | |
1431 | % | |
1432 | % \begin{macrocode} | |
1433 | %<*split> | |
1434 | \RequirePackage{sverb} | |
1435 | % \end{macrocode} | |
1436 | % | |
1437 | % \begin{environment}{splitverb} | |
1438 | % \begin{environment}{splitverb*} | |
1439 | % | |
1440 | % The basic environments are simple enough. | |
1441 | % | |
1442 | % \begin{macrocode} | |
1443 | \def\splitverb{\listinghook\sv@readenv\splitverb@} | |
1444 | \expandafter\def\csname splitverb*\endcsname% | |
1445 | {\listinghook\begingroup\@noligs\svsplit@star} | |
1446 | \def\svsplit@star#1{\endgroup\splitverb@{#1}{\end{splitverb*}}} | |
1447 | % \end{macrocode} | |
1448 | % | |
1449 | % \end{environment} | |
1450 | % \end{environment} | |
1451 | % | |
1452 | % \begin{macro}{\splitverb@} | |
1453 | % | |
1454 | % Even this isn't so bad, really. | |
1455 | % | |
1456 | % \begin{macrocode} | |
1457 | \def\splitverb@#1#2{\sv@startlisting\sv@read{#1}\svsplit@line{\svafter#2}} | |
1458 | % \end{macrocode} | |
1459 | % | |
1460 | % \end{macro} | |
1461 | % | |
1462 | % \begin{macro}{\svsplit@line} | |
1463 | % | |
1464 | % For the sake of readability (and maybe saving a few tokens), we define some | |
1465 | % synonyms for \TeX's scratch registers. |\svsplit@remain| will be a | |
1466 | % |\global| register containing the remaining horizontal space on the line; | |
1467 | % |\svsplit@indent| is a local register containing the amount of initial | |
1468 | % whitespace on the line. | |
1469 | % | |
1470 | % \begin{macrocode} | |
e8e9e5d8 | 1471 | \dimendef\svsplit@remain=1 |
3a9729b4 | 1472 | \dimendef\svsplit@indent=2 |
1473 | % \end{macrocode} | |
1474 | % | |
1475 | % The switch |\svsplit@| is set if we've found a good place to split the | |
1476 | % current line. | |
1477 | % | |
1478 | % \begin{macrocode} | |
1479 | \newif\ifsvsplit@ | |
1480 | % \end{macrocode} | |
1481 | % | |
1482 | % And finally a delimiter. This is the same one I use everywhere else. | |
1483 | % | |
1484 | % \begin{macrocode} | |
1485 | \def\q@delim{\q@delim} | |
1486 | % \end{macrocode} | |
1487 | % | |
1488 | % \begin{macrocode} | |
1489 | \begingroup | |
1490 | \catcode`\~=\active \lccode`\~=32 | |
1491 | \catcode`\!=\active \lccode`\!=9 | |
1492 | \lowercase{\endgroup | |
1493 | % \end{macrocode} | |
1494 | % | |
1495 | % So far, so good. The |\svsplit@line| macro is given a line of text. We | |
1496 | % initialize |\svtab| to be a \emph{single} space, |\svsplit@remain| to be | |
1497 | % the text width, and |\svsplit@indent| to zero. Then we embark on the first | |
1498 | % loop, which attempts to find the width of the leading whitespace. | |
1499 | % | |
1500 | % \begin{macrocode} | |
1501 | \def\svsplit@line#1{% | |
1502 | \divide\svtab8% | |
1503 | \global\svsplit@remain\linewidth% | |
1504 | \svsplit@indent\z@% | |
1505 | \sv@emptybox\tw@% | |
1506 | \let\next@\svsplit@findindent% | |
1507 | \next@#1\q@delim% | |
1508 | } | |
1509 | % \end{macrocode} | |
1510 | % | |
1511 | % A straightforward tail-recursive loop finds out how much whitespace there | |
1512 | % is at the start of the current line. Note that |\next@| is already set up | |
1513 | % for the optimized case of continuing the loop. Also, if we reach the end | |
1514 | % then this is a blank line, so only emit something if we didn't see the | |
1515 | % end-marker. This is the only place we need to check for this. | |
1516 | % | |
1517 | % \begin{macrocode} | |
1518 | \def\svsplit@findindent#1{% | |
1519 | \ifx~#1% | |
1520 | \advance\svsplit@indent\svtab% | |
1521 | \else\ifx!#1% | |
1522 | \dimen@8\svtab% | |
1523 | \divide\svsplit@indent\dimen@% | |
1524 | \multiply\svsplit@indent\dimen@% | |
1525 | \advance\svsplit@indent\dimen@% | |
1526 | \else\ifx\q@delim#1% | |
1527 | \if@matched\else\svline\tw@\fi% | |
1528 | \let\next@\relax% | |
1529 | \else% | |
1530 | \def\next@{\svsplit@scanline{#1}}% | |
1531 | \fi\fi\fi% | |
1532 | \next@% | |
1533 | } | |
1534 | % \end{macrocode} | |
1535 | % | |
1536 | % Now we have to actually scan the line to find breakpoints. We build the | |
1537 | % current unbreakable chunk in |\box|~0. When we find a breakpoint, we close | |
1538 | % the box, maybe stretch it to take into account trailing space, and attach | |
1539 | % it to |\box|~2, which is gathering the current line. If |\svsplit@remain| | |
1540 | % hits zero then we flush |\box|~2 to the output and continue on the next | |
1541 | % line with a (more-or-less) clean slate. | |
1542 | % | |
1543 | % If there's no breakpoint then we're hosed. In that case, we just insert a | |
1544 | % (|\normalfont|) hyphen and eject what we've got. | |
1545 | % | |
1546 | % Note that this assumes that the indentation will fit. If not, then we're | |
1547 | % deeply stuffed. | |
1548 | % | |
1549 | % \begin{macrocode} | |
1550 | \def\svsplit@scanline{% | |
1551 | \svsplit@false% | |
1552 | \let\next@\svsplit@char% | |
1553 | \setbox\z@\hbox\bgroup% | |
1554 | \kern\svsplit@indent% | |
1555 | \global\advance\svsplit@remain-\svsplit@indent% | |
1556 | \next@% | |
1557 | } | |
1558 | % \end{macrocode} | |
1559 | % | |
1560 | % Scanning a character isn't so bad, if we take it a step at a time. | |
1561 | % | |
1562 | % \begin{macrocode} | |
1563 | \def\svsplit@char#1{% | |
1564 | % \end{macrocode} | |
1565 | % | |
1566 | % If the character is a space or a tab, then we call |\svsplit@space| which | |
1567 | % knows about adding breakable whitespace. For tabs, this involves computing | |
1568 | % the correct tab size. | |
1569 | % | |
1570 | % \begin{macrocode} | |
1571 | \ifx~#1% | |
1572 | \svsplit@space\svtab% | |
1573 | \else\ifx!#1% | |
1574 | \@tempdima\linewidth% | |
1575 | \advance\@tempdima-\svsplit@remain% | |
1576 | \@tempdimb\@tempdima% | |
1577 | \dimen@8\svtab% | |
1578 | \divide\@tempdimb\dimen@% | |
1579 | \multiply\@tempdimb\dimen@% | |
1580 | \advance\@tempdimb\dimen@% | |
1581 | \advance\@tempdimb-\@tempdima% | |
1582 | \svsplit@space\@tempdimb% | |
1583 | % \end{macrocode} | |
1584 | % | |
1585 | % We might have reached the end of the line. If so, then we finish off. | |
1586 | % | |
1587 | % \begin{macrocode} | |
1588 | \else\ifx\q@delim#1% | |
1589 | \let\next@\svsplit@done% | |
1590 | % \end{macrocode} | |
1591 | % | |
1592 | % Otherwise it's a normal character. If there's not enough space then force | |
e8e9e5d8 | 1593 | % a break. |
3a9729b4 | 1594 | % |
1595 | % \begin{macrocode} | |
1596 | \else% | |
1597 | \ifdim\svsplit@remain<2\svtab% | |
1598 | \ifsvsplit@\else\normalfont-\svsplit@break\fi% | |
1599 | \svsplit@eject% | |
1600 | \fi% | |
1601 | % \end{macrocode} | |
1602 | % | |
1603 | % Insert the character and decrement the distance-left register. | |
1604 | % | |
1605 | % \begin{macrocode} | |
1606 | #1% | |
1607 | \global\advance\svsplit@remain-\svtab% | |
1608 | % \end{macrocode} | |
1609 | % | |
1610 | % Now we see if it's a breakable-after character and if so mark it as being | |
1611 | % breakable. | |
1612 | % | |
1613 | % \begin{macrocode} | |
1614 | \def\temp@##1#1##2\q@delim% | |
1615 | {\ifx\q@delim##2\q@delim\else\svsplit@break\fi}% | |
1616 | \expandafter\temp@\svsplitchars#1\q@delim% | |
1617 | % \end{macrocode} | |
1618 | % | |
1619 | % And with that, we're done. | |
1620 | % | |
1621 | % \begin{macrocode} | |
1622 | \fi\fi\fi% | |
1623 | \next@% | |
1624 | } | |
1625 | % \end{macrocode} | |
1626 | % | |
1627 | % Our next macro is the break-insertion subroutine, which is quite easy. | |
1628 | % | |
1629 | % \begin{macrocode} | |
1630 | \def\svsplit@break{% | |
1631 | \egroup% | |
1632 | \sv@addtobox\tw@\z@% | |
1633 | \svsplit@true% | |
1634 | \setbox\z@\hbox\bgroup% | |
1635 | } | |
1636 | % \end{macrocode} | |
1637 | % | |
1638 | % Now we add space to the current box. The argument is a dimen register. | |
1639 | % | |
1640 | % \begin{macrocode} | |
1641 | \def\svsplit@space#1{% | |
1642 | \ifdim\svsplit@remain>#1\kern#1\global\advance\svsplit@remain-#1\fi% | |
1643 | \svsplit@break% | |
1644 | \ifdim\svsplit@remain>#1\else\svsplit@eject\fi% | |
1645 | } | |
1646 | % \end{macrocode} | |
1647 | % | |
1648 | % We now come to a slightly involved piece of code, which is how to flush out | |
1649 | % a line, and then fix up the registers for the next line correctly. | |
1650 | % | |
1651 | % \begin{macrocode} | |
1652 | \def\svsplit@eject{% | |
1653 | \egroup% | |
1654 | \svline\tw@% | |
1655 | \sv@emptybox\tw@% | |
1656 | \svsplit@false% | |
1657 | \setbox\z@\hbox\bgroup% | |
1658 | \kern\svsplit@indent% | |
1659 | \global\svsplit@remain\linewidth% | |
1660 | \global\advance\svsplit@remain-\svsplit@indent% | |
1661 | \global\advance\svsplit@remain-\wd\z@% | |
1662 | \unhbox\z@% | |
1663 | } | |
1664 | % \end{macrocode} | |
1665 | % | |
1666 | % Finally, how to finish the line and go home. | |
1667 | % | |
1668 | % \begin{macrocode} | |
1669 | \def\svsplit@done{% | |
1670 | \egroup% | |
1671 | \sv@addtobox\tw@\z@% | |
1672 | \svline\tw@% | |
1673 | } | |
1674 | % \end{macrocode} | |
1675 | % | |
1676 | % End the |\lowercase| hack. | |
1677 | % | |
1678 | % \begin{macrocode} | |
1679 | } | |
1680 | % \end{macrocode} | |
1681 | % | |
1682 | % \end{macro} | |
1683 | % | |
1684 | % Finally, set the breakable characters to something plausible. | |
1685 | % | |
1686 | % \begin{macrocode} | |
1687 | \def\svsplitchars{:/.} | |
1688 | % \end{macrocode} | |
1689 | % | |
1690 | % And with that, we're done! | |
1691 | % | |
1692 | % \begin{macrocode} | |
1693 | %</split> | |
1694 | % \end{macrocode} | |
1695 | % | |
86f6a31e | 1696 | % \hfill Mark Wooding, \today |
1697 | % | |
1698 | % \Finale | |
1699 | % | |
1700 | \endinput |